# Quantum logic gates

This is one of the most important sections. We discuss all the quantum logic gates that will be later used to construct quantum circuits. We will see the programming aspects of these quantum gates in *Chapter 6*, *Silq Programming Basics and Features*.

One of the most important properties of quantum logic gates is that they are all unitary, which means they are reversible and there is no loss of information. All the gates preserve the complex vector space transformations, which means if you apply a rotation in the X axis of the Bloch sphere to reach the state |1> from |0>, then the complex conjugate of the gate will help you to reverse the transformation that you did to the Bloch sphere, which means you will return to state |0>. This means there is no loss of information, and from the output of the quantum gates you will be able to find out the inputs as well.

Since we now know the fundamental difference between quantum gates and classical gates, let...